Fountain blade assembly



Feb. 8, 1955 E. A. LUSCOMBE 2,701,523

FOUNTAIN BLADE ASSEMBLY Filed April 26, 1951 INVEN TOR.

Edgarfl. Luscombe' BY Un tat s Par FOUNTAIN BLADE f Edgar A. Luscombe, La Grange, Ill., assignor to Miehle Y Printing Press and Manufacturing Company, Chicago, 11]., a corporation of Delaware Application April 26, 1951, Serial No. 222,990

1 Claim. (Cl. 101-364) This invention relates to improvements in structures such as are applicable, for example, to ink fountains of printing presses. The improvement is more specifically directed to a method of securing the fountain blade i. e., the ink metering member, to its backing plate so as to form an integral part.

Heretofore, it has been the general accepted practice of many manufacturers of printing machinery to secure the ink metering blade in its position on the backing plate by means of rivets. Broadly speaking, this conventional practice has proven satisfactory, but it does involve certain serious disadvantages. For example, it imposes restrictions as to the thickness of the blade to be used, and because of the degree of machining necessary after riveting, the hardness of the blade has to be limited in order to maintain a certain machineability of the metal.

It has also been found that the method of assembling the ink fountain blade to its backing plate or support with rivets, invariably induces strains in the blade and often causes warping thereof which results in troublesome operation on presses in the field. These strains are reflected in erratic action of the fountain blade during adjustment and they prevent uniform response of the blade for relative movements of the adjusting screws.

Experience has also proven that these strains are substantially more apparent when thin blades of less than .040 of an inch, for example, are used. Consequently, it has been necessary to employ blades of a heavier gauge for this purpose thereby sacrificing the inherent advanttageis of greater sensitivity and flexibility of a thinner la e.

It is a primary object of my invention, therefore, to provide a method of and means for assembling an ink fountain blade to its backing plate whereby internal stresses and warping of the blade are eliminated.

Another object of my invention is to provide a method of assembling an ink fountain blade whereby comparatively thin, highly sensitive blades, can be used which will respond uniformly to adjustments.

A further object of this invention is to provide a method of producing an ink fountain blade assembly which will permit the use of a relatively harder, thinner, and therefore, more serviceable blade.

Further objects and advantages will become apparent from the specification when read in conjunction with the accompanying drawings wherein I have graphically depicted the article of manufacture resulting from carrying out the method which forms the basis of my invention. It will be understood, of course, that the same principle can be applied to devices other than ink fountain blades, without departing from the spirit of. the invention. In the drawings,

Figure l is a sectional view showing a conventional ink fountain assembly of a printing press;

Figure 2 is an enlarged sectional view showing the manner in which the fountain blade is bonded to its backing plate, while Figure 3 is a perspective view of the blade assembly.

As is disclosed in Figure 1, of the drawings, this invention is illustrated, merely by way of example, in connection with a conventional printing press ink fountain having a frame member 10, side walls 11, a fountain roller 12, which rotates intermittently to transfer ink to an associated ductor roller, and a bottom wall 13. The bottom wall is preferably pivoted on the frame member by means of the studs 14 and can be rocked from an operative position, as shown, to an inoperative position ice - 2 wherein the fountain assembly :is snore accessible for cleaning.

An ink metering or fountain blade 16, having a backing plate :L7 :seeured thereto, see Figure 3, :is zfastened to the bottom walll3 with .atseries-of ,bolts .18, see Figure 2, and with its free or ink metering edge 19, in close proxtotheLfountainrollerlZ. 4 I

In order to adjust the relative position of the metering edge 19 of the blade 16 with respect to the roller 12, a series of thumb screws 21 are provided which are threaded through the bottom wall 13 with their free ends in contact with the under surface of the blade 16 and near to its metering edge 19.

When a press is in operation, a supply of ink is deposited in the pocket formed by the roller 12, sidewalls 11 and the blade 16 and through the intermittent rotation of the roller 12 in clockwise direction, a predetermined amount of the ink is transferred to the distributing roller system and thereby to the form for each impression or cycle of operation.

In order to achieve the best results, especially when the form consists of half-tones and solids combined, it is imperative that the metering edge 19 of the blade 16 be adjusted within very close limits to control the amount of ink on the fountain roller 12 in accordance with the requirements of the form at any particular spot.

For this reason, it is desirable to have a comparatively thin, highly sensitive fountain blade, which should be of such hardness and flexibility as to permit the finest adjustments and assure long service. Heretofore, these objectives could not be attained because of the method used for assembling the fountain blade 16 to its backing plate 17 Prior to this invention, it has been the practice to rivet the blade assembly together, but this method induced strains in the blade which resulted in troublesome operation of the fountain when the press was in operation. Furthermore, because of the fact that these strains be came progressively more apparent as the thickness of the blade was reduced, it has been necessary to use thick blades which are less sensitive to adjustments.

Moreover, it has also been necessary to finish machine the assemblies after riveting and therefore, the hardness of the blade had to be limited.

With this invention, however, all of these limitations agii objections are overcome and finer results are obtaina c.

As shown in Figure 2, the blade 16 is cemented to its backing plate 17 by means of a thermo-setting resin compound 22 which is a thin film of approximately .004 of an inch thickness, but which has been shown greatly enlarged for illustration purposes.

In assembling the blades and their backing plates by this method the mating surfaces are first finished to General Electric Roughness Specimen E or smoother. They are then cleaned thoroughly with a suitable degreasing compound and assembled with a film of heat reactive bonding cement therebetween. After assembly with the bonding film, a uniform pressure of approximately 70 lbs. per square inch is applied and the assembly, while still under pressure, is then heated to a temperature of 400 F. for about 1% hours. It is then allowed to cool to room temperature before the pressure is released.

When this process is completed, the blade and its backing plate are securely bonded together as an integral unit which will withstand any of the forces to which it is normally subjected. Furthermore, there will be no induced strains in the blade, regardless of its gauge and since there is no finish machining required, the blade can be of any hardness.

While I have herein dis-closed a preferred example of my invention, I do not wish to be limited to specific details as variations in the steps of the process may be employed without departing from the spirit of the invention or the scope of the appended claim.

I claim:

An ink metering assembly for the ink fountains of printmg presses, comprising a thin, flexible hardened metal blade, a bottom wall, a rigid, relatively narrow backing member for said blade, means for securing the backing member to said wall, and means for adjusting the position of said blade thereby 'metered, the lower rear portion ofsaid blade being bonded vary the volume of ink to said backing member by thermo-setting material to thereby present an uninterrupted top surface, and whereby the projecting, flexible portion of said blade is maintained 5 free of induced stresses and strains. 1

i 2 References Cited in the file of this patent 1 UNITED STATES PATENTS m I 843,483 McGovern Feb.- 5, 1907 a am.

Lestner Buschmann Blessing Marshall Peyrebrune Foster Strother et al. Barber Greenway eb. 19, 1907 Apr. 21,1931 Oct. 27, 1931 July 18, 1939 Feb. 8, 1944 June 13, 1944 v July 15, 1947 Ian. 25, 1949 

